A) 56% paid by top 4 countries. Remaining share of 2 of the top 6 = 11.8%.
Doesn't talk about country X at all. Insufficient.
B) If country X is in top 6 (and worst case, 6th), other countries would have paid at least a little more than it. 4.8*6 = 28.8 is much less than 67.8% of the top 6 countries. At the same time, if the top countries in top 6 have paid much more than 4.8%, then X could be in top 6. But in the absence of that information, Insufficient.
Combining A and B,
56% paid by top 4. Thus remaining 2 have to pay 11.8. X is not necessary to be in 5th or 6th spot with 4.8% because there can be two countries with 5.9% each, in which case X can be 7th (or lower). At the same time, the 5th can be something like 7% in which case X can be the 6th.
Who says elephants can't dance?